A session timeout lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, the GNOME desktop can be configured to identify when a user's session has idled and take action to initiate a session lock.
Note: This requirement assumes the use of the RHEL 10 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is not applicable.
Verify RHEL 10 initiates a session lock after a 15-minute period of inactivity for graphical user interfaces with the following command:
$ sudo gsettings get org.gnome.desktop.session idle-delay uint32 900
If "idle-delay" is set to "0" or a value greater than "900", this is a finding.
Fix
Configure RHEL 10 to initiate a screensaver after a 15-minute period of inactivity for graphical user interfaces.
Note: The example below is using the database "local" for the system. If the system is using another database in "/etc/dconf/profile/user", the file should be created under the appropriate subdirectory.
Update the "/etc/dconf/db/local.d/00-screensaver" file to prevent nonprivileged users from modifying the screensaver idle-delay setting:
$ sudo vi /etc/dconf/db/local.d/00-screensaver
[org/gnome/desktop/session] # Set the lock time out to 900 seconds before the session is considered idle idle-delay=uint32 900